ALBERT

Description: Introduction: Allogeneic stem cell transplantation is a potentially curative treatment for patients with high-risk non-Hodgkin lymphoma (NHL). Fludarabine/busulfan based conditioning regimens are widely used in Europe for this purpose. Busulfan dose intensity discriminates between reduced intensity (FB2, 2 days of busulfan at 4 mg/Kg/d per os or 3.2 mg/kg/d iv) and reduced-toxicity myeloablative (FB3/FB4, 3 or 4 days of busulfan at 4 mg/Kg/d per os or 3.2 mg/kg/d iv) conditioning regimens (Bacigalupo, 2009). While some data have been recently published showing some advantages of higher busulfan dose intensity for myeloid malignancies, there is no such data available in the lymphoid setting. Methods: This was a large retrospective study conducted on behalf of the SFGM-TC including all adults allografted in France between January 2004 and December 2014 for NHL (n=378). Clinical data were obtained through ProMISe (Project Manager Internet Server), an internet-based system shared by all French transplantation centers. We aim to compare various outcomes (overall (OS) and lymphoma free (LFS) survivals, relapse incidence (RI), non-relapse mortality (NRM), acute and chronic GVHD) between those who received FB2 (n=277) or FB3/FB4 (n=101) as conditioning regimens. GVHD free relapse free survival (GRFS) was also studied (defined as alive with no previous grade III-IV aGvHD, no moderate or severe chronic GvHD (cGvHD) and no relapse). Results: Both groups were comparable for the following variables: median follow-up (FB2: 24.9 vs FB3/4: 23 months), gender (male 61% vs 53%), disease type (low-grade lymphoma 25% vs 21%, mantle-cell lymphoma 17% vs 13%, high-grade lymphoma 25% vs 21%, T cell lymphoma 32% vs 45%), disease status at transplant (complete remission/very good partial response 64% vs 62%, partial response 28% vs 31%, active disease 8% vs 7%), donor type (sibling 43% vs 49.5%, matched unrelated 56% vs 47), median number of previous courses of treatment (2 vs 2, p=0.44), stem cell source (peripheral blood 96% vs 95%). FB2 patients were significantly older (median 57.3 vs 53.1 years, p=0.07), have been transplanted more recently (median year of transplant: 2011 vs 2010, p=0.001) and have been more previously autografted (69% vs 50.5%, p=0.001). FB3/4 patients have been allotransplanted earlier during the evolution of their disease (median time between diagnosis and allograft 18.2 vs 33.8 months, p=30 months), there were also no significant differences between both groups in terms of OS, LFS, RI or NRM. In multivariate analysis there was a trend for worse outcome using FB3/FB4 regimens (OS: HR 1.46, 95%CI: 0.96-2.23, p=0.07; LFS: HR: 1.43, 95%CI: 0.99-2.06, p=0.05; RI: HR 1.54; 95%CI: 0.95-2.48, p=0.07). These results were also confirmed using a propensity score-matching strategy including 184 FB2 and 98 FB3/4 patients. Conclusion: This large retrospective study showed that reduced toxicity myeloablative fludarabine/busulfan regimens did not improve outcomes of adults allografted for NHL. FB2 conditioning regimen still should be considered as the standard of care conditioning regimen in this setting. To validate these results, prospective studies are needed, like the French prospective trial currently ongoing for myeloid diseases (NCT01985061). Also, new conditioning regimens and post-allograft strategies should be tested to improve outcomes of patients. Disclosures Peffault De Latour: NOVARTIS: Consultancy, Honoraria, Research Funding; PFIZER: Consultancy, Honoraria, Research Funding; ALEXION: Consultancy, Honoraria, Research Funding.

Description: Introduction. Chronic lymphocytic leukemia (CLL) has typically an indolent course but can undergo transformation into a more aggressive lymphoma so called Richter's syndrome. While the advent of novel targeted therapies is transforming the management of patients with CLL, these drugs failed to prevent the risk of RS. RS is associated with a very poor outcome and is thus becoming the main obstacle to long term CLL control. Autologous (auto-) and allogeneic (allo-) hematopoietic stem-cell transplantation (-SCT) have been recommended as the treatment of choice in eligible patients with clonally related RS (Rossi Blood 2018) but previous experience is still limited to less than 50 cases. We here aimed to investigate the safety and efficacy of both auto- and allo-SCT for patients with RS in a large cohort in a period overlapping the advent of novel agents. Methods. We report on a retrospective study of consecutive adult patients with RS who underwent auto- or allo-SCT between 2008 and 2018 in EBMT centers. Results. A total of 197 patients (M/F= 133/64) were included in the present study; 125 patients received allo-SCT and 72 auto-SCT. The main difference between these 2 cohorts was the median age at transplant that was lower in the allo- than in the auto-SCT group (median age 57 [18-71] vs 61 [39-74] years, p = 0.006). Regarding the allo-SCT cohort, median time from RS diagnosis to SCT was 10 months [1.1-322.8] and 54.2% had received 〉2 therapeutic lines for RS. At allo-SCT, 60 (48.4%) were in CR and 53 (42.7%) in PR or SD. Most patients received reduced intensity conditioning (RIC) regimen (n= 90, 72.6%) and peripheral blood (89.6%) as stem cell source. Donors were related (matched, n=40 (33%) or mismatched, n=4 (3%)) or unrelated (matched, n= 76 (61%) and mismatched, n=4 (3%). A total of 41 patients (33.6%) received total body irradiation (TBI). With a median follow-up of 48 months, 2-year OS was 46% (36-55%) and 2-year PFS 38% (28-48%). Two-year cumulative incidence of relapse (CIR) was 31% (22-40%) as was the 2-year NRM (Figure 1). Two-year CIR was significantly reduced in patients with ≤2 therapeutic lines for RS (12% (1-22%) vs 41% (26-55%); p=0.005). Performance status affected 2-y PFS (24% (7-42%) if Karnofsky index

Description: Objectives: In patients with refractory chronic lymphocytic leukemia (CLL), the potential to cure is unique to allogeneic stem cell transplantation (HSCT). Clearance of minimal residual disease by suspected graft-versus-leukemia effects has been described elegantly and documented in several independent patient cohorts. Yet data from large numbers of patients which support the concept of cure by allogeneic transplantation have not been published. With the advent of new targeted therapies for patients with advanced chemo-refractory CLL, this information becomes crucial for clinical decision making and patient counselling. Therefore, we aimed at the description of long-term survival outcomes, and the estimation of excess mortality compared to the age- and sex-matched general population. Patients and Methods: Data from patients with CLL who had received a first allogeneic HSCT from an HLA-identical sibling (SIB) or alternative donor between January 2000 and December 2010, and who were registered with the EBMT database, were analyzed. Patients with Richter's syndrome and with syngeneic donors were excluded from this analysis. Survival probabilities were calculated by means of the Kaplan-Meier estimator both in the total population, and in patients who passed the 2- and 5-year landmark without previous relapse or progression. Excess mortality of the landmark populations compared to an age-, sex- and calendar year-matched general population was estimated with a Cox regression model for relative survival using the R-package relsurv. Results: In total 2589 patients were included into the analysis. The median follow-up of patients alive at the end of follow-up was 4.0 years (range: 1 to 161 months). The median age at HSCT was 55 years (range: 12 to 74 years). One hundred and fifty eight patients (6.1%) were below 40 years of age at the time of transplantation. Seventy-four percent of patients were male. The remission status at the time of transplantation was reported as complete remission in 15%, partial remission in 47%, and stable disease or progressive disease in 32%. Information on the remission status was not available for 6% of the patients. Fifty-one percent of the patients had an HLA-matched sibling donor and seventy-seven percent of patients received reduced-intensity conditioning. For the whole cohort of patients, the 5- and 10-year overall survival (OS), progression-free survival (PFS), and non-relapse mortality (NRM) were 45%, 35%, 36%, and 35%, 28%, 40%, respectively. The cumulative incidence of relapse (CIR) was 21% at two years, 29% at five years, and 32% at ten years. A total of 1023 patients and 394 patients were alive without relapse or progression, and in follow-up at two and five years after HSCT. Five years after patients had passed the 2- and 5-year landmark, OS, CIR and NRM were 73%, 22%, 16%, and 83%, 11%, 10% respectively. Compared to the general population excess mortality of the 5-year landmark population in the subsequent five years was estimated to be 3% for male patients at an age of 45 years, 10% for male patients at an age of 55 years, and 24% for male patients at an age of 65 years (see Figure 1). For female patients in this 5-year landmark population, the corresponding excess mortality rates were 4%, 11%, and 27%. Patients without progression and with CR at any time from HSCT to the two and five-year landmarks had a slightly better outcome than those who had never had CR. Surprisingly, this was not a result of a lower CIR but of a lower NRM. Conclusion: Long-term follow-up data derived from the EBMT registry show a steady decline in hazard of relapse after allogeneic HSCT, yet relapse continues to be a threat. Moreover, even patients alive and disease-free after 5 years are still confronted with substantial NRM. These results show that there is room for improvement of long-term patient care. By comparing mortality of younger patients who passed the 5-year landmark with the general population, only marginal excess mortality was observed, while elderly patients still had substantial excess mortality beyond this landmark. Nevertheless, the results indicate that a significant fraction of patients can be cured by allogeneic HSCT. Figure 1 Figure 1. Disclosures No relevant conflicts of interest to declare.

Description: Introduction Myeloproliferative Neoplasm (MPN) unclassifiable (MPN-U), is a heterogeneous disease that presents with an MPN-type clinical/ histological phenotype yet fails to meet diagnostic criteria for other MPN entities. Incidence is

Description: Abstract 4558 Myeloid Sarcoma (MS) is a rare malignant disorder usually presenting as an extramedullary myeloid cell tumor proliferation. MS can be observed in 3 to 7% of AML cases (called “leukemic” MS, LMS hereinafter). MS prognosis is rather poor with overall survival (OS) not exceeding 2 years. We have previously shown, that allo-SCT following an AML-like chemotherapy is likely the best available therapeutic option for patients with LMS (J Clin Oncol 2008). However, it is still unclear whether allo-SCT is a valid therapeutic option for patients with isolated MS (IMS). The aim of this analysis was to assess the role of allo-SCT in patients with IMS as compared to patients with LMS. We retrospectively analysed the outcome of 99 MS patients with a median age of 40 years (range: 18–70), including 30 cases of IMS and 69 cases of LMS, reported to the EBMT registry between January 1991 and June 2009. The majority of patients were in complete remission (CR) at time of transplant (IMS: first CR n=14, second CR or beyond n=7 vs. LMS: first CR n=38, second CR or beyond n=21, P=0.20). In this series, patients received either a standard (IMS, n=24 vs. LMS, n=55, P=NS) or a reduced-intensity conditioning regimen (IMS, n=6 vs. LMS, n=14, P=NS) prior to allo-SCT from a matched-related (IMS n=21 vs. LMS, n=48, P=NS) or unrelated donor (IMS, n=9 vs. LMS, n=21, P=NS). After allo-SCT, engraftment was observed in all patients. The incidences of grade 2–4 and grade 3–4 acute GVHD were 32% and 9%, respectively. The incidence of chronic GVHD at 2 years was 45%. With a median follow-up of 48 (range: 6–213) months, the 5-years OS, and leukaemia-free survival (LFS), and the cumulative incidences of relapse (RI), and non-relapse mortality (NRM) were 48%, 36%, 40% and 19%, respectively. When comparing the two sub-groups (IMS vs. LMS), there were no significant differences in term of outcomes: neutrophils recovery (15 vs 18.5 days), grade 2–4 acute GVHD (27% vs 35%), chronic GVHD (54% vs 41% at 2 years), 5-year OS (33% vs. 48%), 5-year LFS (30% vs. 38%), 5-year RI (45% vs. 38%) and 5-year NRM (19% vs. 17%). In all, we conclude that allo-SCT is an effective treatment for patients with MS. The current data suggest that patients with isolated or leukemic MS have similar outcome after allo-SCT. Therefore, allo-SCT is likely to be considered as the optimal therapy for both isolated and leukemic MS. Disclosures: Tilly: Amgen: Honoraria.

Description: Patients with relapsed or refractory (R/R) Hodgkin Lymphoma (HL) after first autologous stem cell transplantation (ASCT1) may be offered several therapeutic options. New agents such as brentuximab vedotin or checkpoint inhibitors have recently been approved for the treatment of these patients, however, their efficacy to provide long-term control or cure is still unknown. Thus, a significant proportion of patients are still considered candidates for a second hematopoietic stem cell transplantation, usually an allogeneic transplantation. A second ASCT (ASCT2) has historically been considered as an option only in a small group of patients so the published experience is scarce. We retrospectively evaluated the outcome of 56 adult patients (25% female/75% male) with R/R HL registered in the EBMT database who received an ASCT2 between 2005 and 2014. Planned tandem ASCT were excluded. The median age at ASCT2 was 33 years (range, 19-71) and most patients (n=46, 87%) had a Karnofsky performance score ≥80%. Forty (73%) and 9 (16%) patients were in complete remission (CR) and partial remission (PR), respectively, at day 100 after ASCT1. Twenty-six (46%) relapsed within 12 months after ASCT1. Patients received a median of 1 (0-5) treatment lines between ASCT1 and ASCT2. Of note, only 2 patients received brentuximab vedotin after ASCT1 and none of the patients in our series received checkpoint inhibitors as salvage after ASCT1. The median interval from relapse/progression to ASCT2 was 9.7 months (1.7-89.3). At the time of ASCT2, 38 (69%) patients had chemosensitive disease (20 of them CR; and 18 PR). Most patients (n=43, 77%) received BEAM as the conditioning regimen for ASCT1, whereas preparative regimens for ASCT2 were more heterogeneous (BEAM or similar in 27, 48%; CBV or similar in 8, 14%; and others in 21, 37%). The median time to neutrophil (〉0.5x109/L) and platelet (〉20x109/L) recovery after ASCT2 were 11 (IQR 9-12) and 12 (IQR 10-15) days, respectively. Best response at day 100 following ASCT2 included CR in 29 (52%) patients and PR in 7 (12%); 3 (5%) had stable disease, and 3 (5%) progressed. Twenty-nine (52%) patients are currently alive, with a median follow-up for surviving patients of 73 months (2-153). Causes of death were HL progression (n=21, 79%), ASCT2 toxicity (n=3, 11%), secondary neoplasia (n=1, 3.7%), and unknown (n=2, 7%). The 4-year non-relapse mortality (NRM) was 5% (95% CI 1-14%). The 4-year cumulative incidence of disease progression/relapse was 69% (95% CI 54-80%). The 4-year overall survival (OS) and progression free survival (PFS) were 63% (95% CI 51-77%) and 25% (95% CI 16-41%). In univariate analysis, HL relapse within 12 months of ASCT1 was associated with a worse 4-year OS (44% vs. 79%, p=0.016) and PFS (16% vs. 33%, p=0.033). Chemosensitivity at ASCT2 predicted for better outcomes (4-year OS 78% vs. 30%, p=0.002; PFS 34% vs. 6%, p=0.004). Our series is the largest thus far reported of ASCT2 for patients with R/R HL after ASCT1. NRM is lower than that observed after allogeneic transplantation in this setting; however, relapse remains a major issue, especially for patients who relapse in less than one year after ASCT. For this population, a second ASCT should not be considered, whereas ASCT2 in patients with long response duration after ASCT1 might be appropriate in selected cases. The role of ASCT2 for those patients treated with new drugs such as brentuximab vedotin and checkpoint inhibitors deserves further investigation. Disclosures Martinez: BMS: Research Funding; Takeda: Consultancy. Sureda:BMS: Consultancy, Honoraria; Sanofi: Honoraria; Takeda: Consultancy, Honoraria, Speakers Bureau; Roche: Honoraria; Merck: Consultancy, Honoraria.

Description: Key Points Matching for MICA significantly reduces the incidence of acute and chronic GVHD in otherwise HLA 10/10-matched unrelated-donor HCT. Our results formally define MICA as a novel major histocompatibility complex-encoded human transplantation antigen.

Description: Although efficacy of thalidomide (thal) monotherapy in relapsed/refractory Multiple Myeloma (MM) is proven, the optimal duration of treatment is unknown. Here, we analysed individual patient data of 852 patients (pts.) with relapsed/refractory MM from 21 centres who received thal monotherapy in a trial or in a compassionate use program. To assess the influence of treatment duration, pts. who discontinued thal because of lack of efficacy, progression or death were excluded, so we analysed only pts. who continued on thal as long as they tolerated it or until the study they were enrolled in was complete. 162 pts. were evaluable; 32 completed the trial, 57 had severe neurotoxicity, 2 severe somnolence, 72 other adverse events leading to discontinuation of thal. The median age was 65 years (interquartile range 58–72), 92 (56%) were male, 96 (59%) had relapsed MM. Sixteen (10%) achieved complete remission (CR), 64 (39%) partial remission (PR), 29 (18%) minimal response, 34 (21%) no change, 9 (6%) had progressive disease, 9 (6%) were unevaluable for response. The median daily dose at 3 months was 200 mg/d (100–400), the cumulative dose after 3 months 23200 mg (9025–34150). Median time to response was 3.6 months (3–7), median treatment duration 5 months (2.3–12). Median event-free survival (EFS) was 16 months (95%CI 12–21), median overall survival (OS) 33 months (95%CI 22–44). In univariate analysis, prognostic factors for EFS/OS were leukocyte/platelet count, haemoglobin, cumulative dose at 3 months, duration of treatment and CR/PR. In multivariate analysis, duration of treatment, CR/PR and platelet count remained independent prognostic factors for EFS/OS. If pts. took thal for ≥ 10 months (n=51), median EFS was 31 (95%CI 14–48) vs 12 (9–14, p

Description: The curative potential of allo-SCT for malignancies derives from the progressive reconstitution of the immune system and the development of effective anti-tumor immunity, but GVHD and disease relapse remain considerable obstacles to improvement in overall outcomes. Because in recipients target antigens are persisting, donor-derived T-cell responses may be expected to lead to the accumulation of a sizable proportion of differentiated T-cells, as happens following infection with persisting pathogens. A few cross-sectional studies have pointed to the preponderance of certain memory T-cell subsets associated with chronic GVHD (cGVHD), but the subset identified differed between studies. Inasmuch as qualitative T-cell recovery takes months to years to complete and there is substantial variability in time to development of GVHD or relapse, serial analysis might be more suitable to unveil early changes in T-cell subset composition attributable to transplantation-related events. From October 2003 on, 55 pts who underwent an allo-SCT after myeloablative conditioning were monitored prospectively in terms of clinical post-graft complications, including graft rejection, infections, GVHD and relapse. Blood samples were obtained on days 30±2, 60±3, 90±5, 180±10 and 365±15 post-transplant. Naive (CD45RA+CCR7+), central memory (TCM, CD45RAnegCCR7+), effector memory (TEM, CD45RAnegCCR7neg), and terminally differentiated effector (TTD, CD45RA+CCR7neg) were enumerated within the CD4+ and CD8+ pools, and the percentage of cells coexpressing CD28 was calculated within each eight subsets. The degree of donor-derived T-cell chimerism was assessed by real time PCR (sensitivity ≤ 1%). Median follow-up was 733 d (404–1251). Dynamics of CD4+ and CD8+ naive, TCM, TEM, and TTD were similar between the pts who developed cGVHD (n=15) and those who did not and between pts who relapsed and those who did not. However, costaining to detect CD28 demonstrated contrasting differences between cGVHD and relapse. At day 30, pts who subsequently relapsed (n=17) had elevated percentages of cells keeping CD28 expression within CD8+ T-cell subsets (TCM, p=.001; TCM, p=.021; and TTD, p=.007). Conversely, pts who subsequently developed cGVHD (n=15; only one relapsed) had diminished percentages of CD28+ cells within the two CD8+CCR7+ subsets at day 30 (p=.002 and p=.034, respectively). Loss of CD28 expression is known to be a hallmark of CMV infection but multivariate analysis ruled out, however, a confounding effect of CMV. Adjusted hazard ratios were 0.10 (95% CI, 0.01-0.76; p=.026) and 5.56 (95% CI, 1.16-25.00; p=.032) with CD28neg cells 16.7% of all CD8+ TCM at day 30 for relapse and cGVHD, respectively. Furthermore, pts with relapse had more often mixed chimerism at day 30 while those with cGVHD had more often full-donor chimerism (p=.042 and p=.023, respectively). CONCLUSION: This prospective study is the first to associate an early contrasting change in CD8+CD28neg T-cells with the risk of relapse and cGVHD after a myeloablative conditioning. Determination at day 30 of the proportions of CD8+ T-cell subsets expressing CD28 and of the level of T-cell chimerism could assist in predicting risk of relapse and cGVHD and help build an algorithm for the management of immunosuppressive treatment.

Description: The IFM99-03 and IFM99-04 trials were conducted from April 2000 to August 2004. Patients younger than 66 years with high-risk (b2microglobulin 〉 3 and chromosome 13 deletion by FISH analysis at diagnosis) de novo multiple myeloma (MM) were included and prospectively treated. In both protocols, induction regimen consisted of VAD (4 courses) followed by melphalan 200 mg/m2 (HDM200) plus autologous peripheral blood stem cell transplantation (ASCT). When a HLA-sibling donor was available, ASCT was followed by reduced-intensity conditioning regimen (RIC) allograft (fludarabine, antithymocyte globulin and low dose busulfan): IFM9903 protocol (Garban et al, Blood2006;107:3474–3480). When no donor was available, patients were randomised to receive a second ASCT with HDM220 +/− anti-IL6 monoclonal antibody (BE-8, 250 mg total dose, Diaclone Besançon, France): IFM99-04 protocol (Moreau et al, Blood2006;107:397–403).284 patients met eligibility criteria and received at least one course of VAD. 65 had an available HLA-identical sibling donor and were included in the IFM99-03 trial, and 219 were included in the IFM 99-04 trial. Patients were older in the tandem ASCT trial (median age, 58 vs 54 years; P = .006) and the b2-microglobulin level was also higher in the latter group (median, 4.9 mg/L vs 4.1 mg/L; P = .049). At the reference date of July 1st, 2008, on an intent-to-treat basis, considering the entire population of 284 patients, with a median follow-up of 56 months, the EFS did not significantly differ from tandem ASCT to single autograft followed by allo-RIC (median 22 vs 19 months, P = 0.58). Nevertheless, there was a trend for a superior OS in the double ASCT trial (median 48 vs 34 months, P = 0.07). When considering the comparison of the results of the 166 patients /219 who completed the whole tandem ASCT protocol with those of the 46 patients /65 who underwent the entire auto/allo-RIC program, no difference was observed regarding EFS (median 25 vs 21 months, P = 0.88), but there was again a trend for a superior OS in favour of double ASCT (median OS, 57 vs 41 months, P = 0.08), due to a longer survival after relapse in the tandem ASCT arm. These long-term results indicate that, in a subgroup of high-risk patients with de novo MM, a tandem autologous transplant procedure is at least equivalent or even superior to a combination of autologous followed by RIC allogeneic stem cell transplantation.